1. Field of the Invention
This invention relates to the field of computer security. More specifically, the present invention comprises a method for continuously monitoring for the presence of a specific authorized user or users and—if the presence of an authorized user is no longer detected—terminating access to the computer.
2. Description of the Related Art
Various devices exist for preventing the unauthorized access of computers. Most of these devices are directed to lockout mechanisms which prevent an unauthorized user from logging onto a computer.
For example, U.S. Pat. No. 5,960,084 to Angelo describes a method of enabling power to a computer system based upon the results of a two-piece user verification procedure. If the user does not provide the required “smart card” and password, power to the computer system is disabled.
Another example is U.S. Pat. No. 6,338,142 to Alsaadi. Alsaadi's patent discloses a lockout circuit which generates an interfering signal that disrupts the “power on” signal generated by the computer's power controller. The lockout circuit generates this interfering signal when triggered by a triggering device such as an Ethernet chip or a switch.
Yet another example is provided in U.S. Pat. No. 5,712,973 to Dayan et al. Dayan et al.'s patent discloses a security feature which renders a computer system inoperable when an unauthorized user moves the system out of a containment region. To accomplish this, Dayan et al. uses a radiation source, such as a radio frequency transmitter, to transmit radiation with particular characteristics throughout the containment zone. Logic circuitry is provided as part of the system to disable access when the radiation is no longer detected.
Another approach is to use monitoring technology to monitor for the presence of a person near the computer (such as through the use of a motion detector). When such systems determine that no person is present near the computer, the systems log the current user out of the computer. Many other devices are also known in the art. Like the aforementioned security systems, however, none of these devices seek to monitor whether a specific authorized user is still present. The current inventive method remedies this and other deficiencies.